JP7239125B2 - Radiation imaging device - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act Date September 25-26, 2020 (Announcement date: September 25, 2020) Conference name, venue 21st International Young Scientists Conference Optics and High Technology Material Science - SPO 2020 ONLINE Held online [Publication, etc.] Date of publication October 8, 2019 Publication (name of publication, volume number, issue number, corresponding page, place of issue/publisher, etc.) IEEE International Conference on 3D System Integration, 3DIC Papers , Publish to: https://ieeexplore. IEEE. org/document/9058894/metrics#metrics Publisher: IEEE [Publications, etc.] Date October 8-10, 2019 (Announcement date: October 9, 2019) Meeting name and venue IEEE 2019 INTERNATIONAL 3D SYSTEMS INTEGRATION CONFERENCE Miyagino Cultural Center Patna Theater 2-12-70 Olympics, Miyagino-ku, Sendai, Miyagi 983-0842 [Publications, etc.] Date October 13-17, 2019 (Announcement date: 2019 October 16) Meeting name, location 236th ECS Meeting Hilton Atlanta 255 Courtland Street NE, Atlanta, Georgia, 30303, USA [Publications] Date October 26-November 2, 2019 October 30, 2019) Meeting Name, Venue 2019 IEEE NSS-MIC Manchester Central Convention Complex Windmill Street, Petersfield, Manchester, Greater Manchester M2 3GX, England

This disclosure describes a radiation imaging apparatus.

2. Description of the Related Art As a conventional imaging device, a pixel-sharing structure including a plurality of pixels, a charge storage section, and a transistor for reading out pixel signals is known, as described in Patent Document 1 below. In this conventional structure, the charge reservoirs and transistors are shared between multiple pixels. On the other hand, techniques for detecting a two-dimensional distribution of radiation have been developed. Such radiation detection technology is expected to be applied to the medical field, industrial field, security field, and the like. A radiation detector using radiation detection technology generates charges corresponding to the energy of radiation or charges corresponding to the number of particles incident on the detector for each pixel. Then, in a plurality of readout circuits provided corresponding to each pixel, radiation-related information is obtained for each pixel by using the value obtained by integrating the charges or the number of particles.

JP 2018-207291 A

A conventional radiation detector uses a configuration in which a plurality of detectors are arranged for the purpose of expanding the detection area. In such a configuration, there has been a tendency to complicate wiring paths for output from a plurality of detectors having a plurality of pixels to an external circuit board or the like. Therefore, noise may occur in the signals output from the plurality of detectors, or interference may occur between the output signals from the plurality of detectors. Therefore, in conventional radiation detectors, the reliability of information for each pixel that is output may be lowered.
The present disclosure describes a radiation imaging apparatus that can simplify wiring routes and improve reliability of output information.

A radiation imaging apparatus according to one embodiment of the present disclosure includes a plurality of charge generation units that generate charges corresponding to the energy of incident radiation or the number of particles, and a digital radiograph based on the charges generated by each of the plurality of charge generation units. a plurality of reading units for outputting values, radiation detectors stacked and arranged two-dimensionally, and a circuit board on which the plurality of radiation detectors are arranged; is configured to transfer data representing a digital value among the plurality of readout units in response to a control signal from the outside, and then output the data to other adjacent radiation detectors.

In this radiation imaging apparatus, each of the plurality of readout units outputs a digital value based on charges generated by the plurality of charge generation units. At this time, each of the plurality of readout units transfers data representing a digital value within the plurality of readout units in response to a control signal from the outside, and then outputs the data to the adjacent radiation detector. Such a configuration eliminates the need for wiring for outputting data to the outside in at least some of the readout units in the plurality of radiation detectors. As a result, the wiring route for data output is simplified, and the reliability of the output information indicated by the data can be improved.

In one form, the plurality of readout units may be configured to sequentially transfer data representing digital values to other adjacent readout units in response to a control signal from the outside. In this case, each of the plurality of readout units sequentially transfers data representing a digital value to adjacent readout units in response to a control signal from the outside. Such a configuration eliminates the need for wiring for outputting data to the outside in at least part of the readout section in the radiation detector. As a result, the wiring route for data output is simplified, and the reliability of the output information indicated by the data can be improved.

In one form, the plurality of readout units may be configured to transfer data via all readout units included in one radiation detector. In this case, the plurality of readout units transfer data representing digital values via all the readout units in response to a control signal from the outside. Such a configuration eliminates the need for wiring for outputting data to the outside in a larger number of reading units in the radiation detector. As a result, the wiring route for data output is further simplified, and the reliability of the output information indicated by the data can be further improved.

In one aspect, at least one of the readout units at the edge of the radiation detector among the plurality of readout units outputs data transferred from other adjacent readout units to the circuit board in response to the control signal. It may be configured as According to this configuration, since the reading section at the outermost edge outputs the data transferred from the adjacent reading section to the circuit board, the data sequentially transferred via the plurality of reading sections in the radiation detector can be output to the circuit board. , the reading portion at the outermost edge can be output to the circuit board. This eliminates the need for wiring for outputting data from a plurality of readout units in the radiation detector, and effectively reduces the number of wirings connected to one radiation detector. As a result, the reliability of output information can be further improved.

In one embodiment, at least one of the edgemost readout portions of the radiation detector among the plurality of readout portions of the radiation detector is the edgemost readout portion of another radiation detector adjacent to the radiation detector. may be configured to store and forward data output from the . According to this configuration, the readout section at the edge of one radiation detector accumulates and transfers data output from the readout section at the edge of another radiation detector adjacent to the one radiation detector. function as Thereby, wiring for outputting data from other radiation detectors can be shortened. As a result, the reliability of output information can be further improved.

In one form, a further circuit board having a plurality of readouts formed therein, at least one of the outermost readouts transmits data to the circuit board via a through electrode penetrating through the another circuit board. can be output to According to this configuration, the wiring that connects the reading section at the outermost edge and the circuit board can be formed within the range of the charge generating section, and the gap between the plurality of radiation detectors in the radiation imaging apparatus can be reduced. be able to. As a result, it is possible to prevent the occurrence of dead zones in the radiation imaging apparatus.

In one embodiment, the circuit board includes another circuit board in which a plurality of readout sections are formed, and at least one of the readout sections at the outermost edge is provided with a through electrode that passes through the circuit board and the other circuit board. may be entered via According to such a configuration, the wiring that connects the readout section at the outermost edge and the circuit board can be formed within the range of the charge generation section, and the gap between the plurality of radiation detectors 1 can be reduced. can be done. As a result, it is possible to prevent the occurrence of dead zones in the radiation imaging apparatus.

The radiation imaging apparatus of the present disclosure can simplify the wiring route and improve the reliability of output information.

FIG. 1 is a perspective view showing a radiation image sensor according to an embodiment. FIG. 2 is an end view of the radiation image sensor of FIG. 1 taken along line II-II. FIG. 3 is a plan view showing the arrangement of readout circuits 8h in integrated circuit layer 8b of FIG. FIG. 4 is a block diagram showing a configuration of readout circuit 8h of FIG. 3. Referring to FIG. FIG. 5 is a plan view showing an example of the data transfer direction relationship of the radiation detectors 1 arranged two-dimensionally on the circuit board 4 of FIG. FIG. 6 is a plan view showing an example of the data transfer direction relationship of the radiation detectors 1 two-dimensionally arranged on the circuit board 4 of FIG. FIG. 7 is a plan view showing an example of the data transfer direction relationship of the radiation detectors 1 arranged two-dimensionally on the circuit board 4 of FIG. FIG. 8 is a plan view showing an example of the data transfer direction relationship of the radiation detectors 1 arranged one-dimensionally on the circuit board 4 in the modification.

Hereinafter, the radiation imaging apparatus of the present disclosure will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and overlapping descriptions are omitted.
A radiation image sensor 100, which is a radiation imaging apparatus according to the embodiment shown in FIG. 1, obtains a two-dimensional image based on radiation arriving from an inspection object. Radiation includes, for example, gamma rays, X-rays, alpha rays, beta rays, and the like. The radiation image sensor 100 has a radiation detector 1 , a processing section 2 , a control section 3 and a circuit board 4 . A radiation image sensor 100 has a plurality of radiation detectors 1 .

The radiation detectors 1 are two-dimensionally arranged on a rectangular plate-shaped circuit board 4 in one direction along the surface thereof and in a direction perpendicular to the one direction. For example, the radiation detectors 1 are two-dimensionally arrayed on the circuit board 4 with a total of nine (3×3). Each radiation detector 1 has a plurality of pixels (charge generators) arranged two-dimensionally along the surface of the circuit board 4, and stores data indicating a pixel value corresponding to incident radiation for each pixel. Output. This radiation detector 1 has one charge generator 7 and one readout circuit board 8 . The shape of the charge generator 7 and the readout circuit board 8 is a rectangular plate. The radiation detector 1 has a laminated structure. One charge generator 7 is provided with one readout circuit board 8 corresponding to the charge generator 7 . Each charge generator 7 is stacked and arranged on the corresponding readout circuit board 8 . As will be described later, each charge generator 7 is electrically connected to the readout circuit board 8 via bump electrodes. The charge generator 7 outputs a signal corresponding to the charge corresponding to the energy of the radiation incident on each of the plurality of pixels. The readout circuit board 8 then processes the charge generated by the charge generator 7 for each pixel. As a result, readout circuit board 8 generates digital signal φ2 as a pixel value for each of the plurality of pixels. The readout circuit board 8 outputs a digital signal φ2 for each of a plurality of pixels to the processing section 2, as will be described later.

The processing section 2 is connected to a plurality of radiation detectors 1 via a circuit board 4 . The processing unit 2 receives the digital signal φ2 for each pixel from each radiation detector 1 . For example, the processing unit 2 outputs a two-dimensional image of all pixels included in the plurality of radiation detectors 1 based on the pixel-by-pixel digital signal φ2 received from the plurality of radiation detectors 1 . The control unit 3 is connected to the multiple radiation detectors 1 via the circuit board 4 . The control unit 3 provides control signals to the multiple radiation detectors 1 .

The configurations of the radiation detector 1 and the circuit board 4 will be described in detail with reference to FIG. FIG. 2 is an end view of the radiation image sensor 100 of FIG. 1 taken along line II-II. As mentioned above, the radiation detector 1 has a charge generator 7 and a readout circuit board 8 .

The charge generator 7 receives radiation such as X-rays. The charge generator 7 generates electron-hole pairs (charge pairs) for each pixel by the received X-rays. That is, the charge generator 7 converts the received radiation into a current signal (charge signal) corresponding to its energy for each pixel. As the charge generator 7, for example, a Cd(Zn)Te charge generator, Si charge generator, Ge charge generator, GaAs charge generator, GaN charge generator, TlBr charge generator, etc. may be used. Alternatively, a device having a scintillator and a photodetector for each pixel may be used as the charge generator 7 . A scintillator converts x-rays into light. The photodetector converts the light generated by the scintillator into electrical charges.

FIG. 2 shows a configuration example of the charge generator 7 when a compound semiconductor such as CdTe is included as a detection element. Thus, the charge generator 7 includes a rectangular flat detection element 7a, a surface electrode 7b, and a plurality of bump electrodes 7c. A surface electrode 7b is formed on the entire radiation incident side surface of the detection element 7a. Bump electrodes 7c, which are protruding electrodes arranged two-dimensionally, are formed on the back surface of the detection element 7a. In the radiation detector 1 having such a structure, each of the plurality of regions of the charge generator 7 facing the bump electrode 7c forms a pixel (charge generating portion). When the radiation image sensor 100 is used, a positive bias voltage is applied from the outside to the surface electrode 7b. As a result, a current signal corresponding to the energy of the radiation incident on each pixel of the detection element 7a is generated, and the current signal is read out to the readout circuit board 8 from the corresponding bump electrode 7c. For example, the bump electrodes 7c are two-dimensionally arranged in 96×96 on the back surface of the detection element 7a. In such a configuration, the radiation detector 1 has 96×96 pixels arranged two-dimensionally.

The readout circuit board 8 converts the charge φ1 into a digital signal φ2, which is a pixel value, based on the current signal output by each pixel of the charge generator 7 . Further, the readout circuit board 8 outputs the digital signal φ2 for each pixel to the processing section 2 . The digital signal φ2 for each pixel contains at least information about the energy of the radiation incident on each pixel.

Specifically, the readout circuit board 8 has a two-layer structure of a wiring layer 8a and an integrated circuit layer 8b. The wiring layer 8a is held in contact with the plurality of bump electrodes 7c of the charge generator 7 on the opposite side of the integrated circuit layer 8b. The wiring layer 8a has therein electric wirings for electrically connecting the plurality of bump electrodes 7c and corresponding readout circuits (details of which will be described later) in the integrated circuit layer 8b. The integrated circuit layer 8b incorporates a circuit group 8c formed with a plurality of readout circuits (readout units) for processing electric signals output from each pixel of the charge generator 7 and outputting a digital signal φ2. . Furthermore, the integrated circuit layer 8b is provided with a through electrode 8d for inputting a signal to the circuit group 8c and a through electrode 8d provided on one end side along the main surface of the integrated circuit layer 8b. A bump electrode 8e for connection, a through electrode 8f provided on the other end side along the main surface for outputting a signal from the circuit group 8c, and the through electrode 8f are electrically connected to the circuit board 4. A bump electrode 8g is provided for this purpose. The through electrodes 8d and 8f penetrate through the integrated circuit layer 8b and are electrically connected to readout circuits (described later) at the outermost edge of the circuit group 8c. Two adjacent radiation detectors 1 are arranged such that the through electrode 8f and the bump electrode 8g provided in one radiation detector 1 are close to the through electrode 8d and the bump electrode 8e provided in the other radiation detector 1. placed in

The circuit board 4 has a plurality of surface electrodes (electric wiring) 4a formed on the surface on which the radiation detector 1 is mounted. The surface electrodes 4a connect the bump electrodes 8e of the radiation detector 1 on the circuit board 4 to the control unit 3 or the bump electrodes 8g of the radiation detector 1 on the adjacent circuit board 4, thereby connecting the bumps of the radiation detector 1 to each other. It is a wiring section for connecting the electrode 8g to the processing section 2 or the bump electrode 8e of the radiation detector 1 adjacent thereto.

Now, with reference to FIGS. 3 and 4, the configuration of the readout circuit in the integrated circuit layer 8b will be described in detail. FIG. 3 is a plan view showing the layout of the readout circuit 8h in the integrated circuit layer 8b, and FIG. 4 shows the configuration of the readout circuit 8h.

As shown in FIG. 3, the integrated circuit layer 8b has a plurality of readout circuits 8h arranged two-dimensionally so as to correspond to the plurality of pixels of the radiation detector 1. As shown in FIG. For example, when the radiation detector 1 has 96×96 pixels arranged two-dimensionally, correspondingly, a plurality of readout circuits 8h arranged two-dimensionally 96×96 have

As shown in FIG. 4, the readout circuit 8h has a signal converter 10 and a memory . That is, one signal converter 10 and one memory 14 are connected to one pixel of the charge generator 7 .
The signal converter 10 is electrically connected to the bump electrode 7c of the corresponding pixel of the charge generator 7 via the wiring layer 8a. The signal converter 10 receives a current signal-based charge φ1 from the corresponding pixel in the charge generator 7 . Then, the signal converter 10 discretizes the analog signal based on the charge φ1 and outputs it as a digital signal. That is, the signal converter 10 is an A/D converter. For example, the resolution of signal converter 10 may be 10 bits. This analog signal is represented as a voltage and corresponds to the energy of the radiation impinging on the corresponding pixel in charge generator 7 .

Memory 14 is connected to signal converter 10 and receives the digital signal from signal converter 10 . The memory 14 stores the digital signal φ2 each time the digital signal is input. Furthermore, the memory 14 is connected to the memory 14 of the readout circuit 8h corresponding to another adjacent pixel. Then, the memory 14 outputs the digital signal φ2 generated by the signal converter 10 to the memory 14 corresponding to another adjacent pixel according to the control signal θ provided from the control unit 3, or Output to the outside (processing unit 2 or adjacent radiation detector 1) via through electrode 8f, bump electrode 8g, and surface electrode 4a. In addition, the memory 14 receives a digital signal φ2 from the readout circuit 8h corresponding to another adjacent pixel, or from the adjacent radiation detector 1 via the surface electrode 4a, the bump electrode 8e, and the through electrode 8d. The resulting digital signal φ2 is sequentially overwritten and saved. Then, according to the control signal, the memory 14 outputs the digital signal φ2 received from another pixel to the memory 14 corresponding to another adjacent pixel, or to the through electrode 8f, the bump electrode 8g, and the memory 14 corresponding to the other adjacent pixel. Output to the outside (processing unit 2 or adjacent radiation detector 1) via surface electrode 4a.

Returning to FIG. 3, the data transfer function by the memory 14 of a plurality of readout circuits 8h included in one radiation detector 1 will be described. The readout circuits 8h corresponding to the plurality of pixels are arranged in one direction (one-dimensional direction) along the surface of the rectangular plate-shaped integrated circuit layer 8b and perpendicular to the one direction so as to correspond to the arrangement of the plurality of pixels. They are arranged two-dimensionally along the other direction. These readout circuits 8h sequentially transfer digital signal .phi.2 to other adjacent readout circuits 8h according to a control signal from control unit 3 (that is, perform serial data transfer). In the following description, the one direction is defined as the X-axis direction, the +X direction is defined as the downward direction, the -X direction is defined as the upward direction, the other direction is defined as the Y-axis direction, the +Y direction is defined as the right direction, and the - Let the Y direction be the left direction.

The plurality of readout circuits 8h in the uppermost column, except for the readout circuits 8h in the left and right outermost columns, receive the digital signal φ2 received from the leftwardly adjacent readout circuit 8h according to the control signal. After sequentially storing, the stored digital signal φ2 is output (transferred) toward the readout circuit 8h adjacent to the right. The readout circuit 8h at the left end of the column receives the digital signal φ2 input from the readout circuit 8h at the edge of the adjacent radiation detector 1 via the surface electrode 4a, the bump electrode 8e, and the through electrode 8d. After receiving and sequentially storing, the stored digital signal φ2 is output (transferred) toward the readout circuit 8h adjacent to the right. The readout circuit 8h at the right end of the column sequentially stores the digital signal φ2 received from the readout circuit 8h adjacent in the left direction, and then outputs it to the readout circuit 8h adjacent in the downward direction, that is, the right end of the column adjacent in the downward direction. The stored digital signal φ2 is output (transferred) toward the readout circuit 8h of the section.

The plurality of readout circuits 8h in the second column adjacent to the endmost column perform an operation in which the data transfer direction is opposite to the above operation. That is, except for the left and right edge readout circuits 8h, the digital signals φ2 received from the rightwardly adjacent readout circuits 8h are sequentially stored according to the control signal, and then the leftwardly adjacent readout circuits 8h are stored. to output the stored digital signal φ2. The readout circuit 8h at the right end of the column sequentially stores the digital signal φ2 output from the readout circuit 8h at the right end of the adjacent column, and then outputs the stored digital signal φ2 to the readout circuit 8h adjacent to the left. Output. The readout circuit 8h at the left end of the column sequentially stores the digital signal φ2 received from the readout circuit 8h adjacent in the right direction, and then outputs the digital signal φ2 to the readout circuit 8h adjacent in the downward direction, that is, the left end of the column adjacent in the downward direction. The stored digital signal φ2 is output toward the readout circuit 8h of the section.

Readout circuits 8h from the third column to the bottommost column have similar data transfer functions. However, the edgemost readout circuit 8h (the rightmost readout circuit 8h in the lowermost column in the example of FIG. 3) that received the last data transfer is the edgemost edge of the other adjacent radiation detector 1. The stored digital signal φ2 is output to the reading circuit 8h or the processing unit 2 via the through electrode 8f, the bump electrode 8g, and the surface electrode 4a.

As described above, the plurality of readout circuits 8h included in one radiation detector 1 has one data input from the adjacent radiation detector 1, and transfers the data via all the readout circuits 8h. After that, it is configured to output to the adjacent radiation detector 1 from the readout circuit 8h, which is one data output. On the other hand, a plurality of readout circuits 8h included in one radiation detector 1 are divided into a plurality of regions, and each of the plurality of divided regions has one data input and one data output, It may be configured to transfer data through all read circuits 8h. Also, each of the plurality of divided regions has one data input and a plurality of data outputs. Data may be output to adjacent radiation detectors 1 from readout circuits 8h, which are a plurality of data outputs.

5, 6, and 7, the relation of the directions of serial data transfer in the plurality of radiation detectors 1 included in the radiation image sensor 100 will be described. 5 to 7 are plan views showing an example of the relationship of the data transfer directions of the radiation detectors 1 two-dimensionally arranged on the circuit board 4. FIG. Here, as in FIG. 4, one direction of the arrangement direction of the radiation detectors 1 is defined as the X-axis direction, the +X direction is the downward direction, the −X direction is the upward direction, and the other direction of the arrangement direction is defined as the X-axis direction. The Y-axis direction is defined, the +Y direction is the right direction, and the -Y direction is the left direction. In this way, the respective radiation detectors 1 are arranged so that their data transfer directions are substantially parallel to each other.

In the example of the transfer direction shown in FIG. 5 , the plurality of radiation detectors 1 in the uppermost row detects radiation adjacent to the left in accordance with the control signal, except for the leftmost radiation detector 1 . A digital signal φ2 received from the device 1 via the surface electrode 4a, the bump electrode 8e, and the through electrode 8d is transferred via a plurality of internal readout circuits 8h. The radiation detector 1 at the left end of the column performs data transfer among a plurality of internal readout circuits 8h according to the control signal. At the same time, except for the radiation detector 1 at the right end, each of the radiation detectors 1 directs the radiation detector 1 adjacent to the right in accordance with the control signal to the reading circuit 8h at the farthest edge. The stored digital signal φ2 is output via the through electrode 8f, the bump electrode 8g, and the surface electrode 4a. The radiation detector 1 at the right end of the column transmits the digital signal φ2 stored by the readout circuit 8h at the outermost edge to the radiation detector 1 adjacent downward to the through electrode 8f, the bump electrode 8g, and the surface electrode. Output via the electrode 4a.

For the plurality of radiation detectors 1 in the second row adjacent to the endmost row, the data transfer direction is opposite to the above operation. That is, except for the readout circuits 8h at the left and right outermost edges, the digital signals φ2 received from the radiation detectors 1 adjacent to the right are transferred between the readout circuits 8h according to the control signal, and at the same time, It outputs the transferred digital signal φ2 toward the adjacent radiation detector 1 . The readout circuit 8h at the right end of the column transfers the digital signal φ2 output from the radiation detector 1 at the right end of the adjacent column between the readout circuits 8h, and at the same time, directs it to the radiation detector 1 adjacent in the left direction. It outputs the transferred digital signal φ2. The radiation detector 1 at the left end of the column transfers the digital signal φ2 received from the radiation detector 1 adjacent in the right direction between the readout circuits 8h and at the same time, transfers it toward the radiation detector 1 adjacent in the downward direction. output a digital signal φ2.

The radiation detectors 1 from the third row to the bottommost row have similar data transfer functions. However, the radiation detector 1 at the farthest edge, which received the data transfer last, transmits the transferred digital signal φ2 toward the processing unit 2 via the through electrode 8f, the bump electrode 8g, and the surface electrode 4a. Output. In this manner, data transfer by daisy-chain connection is realized through all the radiation detectors 1 constituting the radiation image sensor 100 without omission.

The plurality of radiation detectors 1 included in the radiation image sensor 100 are connected in a daisy chain via the surface electrode 4a, the bump electrode 8e, the through electrode 8d, the through electrode 8f, and the bump electrode 8g. It is electrically connected to the controller 3 . As a result, the readout circuits 8h in the respective radiation detectors 1 can simultaneously receive the control signal .theta.

In the example of the transfer direction shown in FIG. 6, the digital signal φ2 is transferred between the plurality of radiation detectors 1 by daisy chain connection in a transfer direction different from the transfer direction shown in FIG. That is, the plurality of radiation detectors 1 in the leftmost column among the columns extending in the vertical direction output the digital signal φ2 from the upper end toward the lower end radiation detectors 1 . Then, for the plurality of radiation detectors 1 in the second row adjacent to the endmost row, an operation is performed in which the data transfer direction is opposite to the above operation, and the radiation detector 1 at the upper end of the row is It outputs the transferred digital signal φ2 toward the radiation detector 1 adjacent to the right. Furthermore, the radiation detectors 1 from the third row to the rightmost row have similar data transfer functions. However, the radiation detector 1 at the farthest edge, which received the data transfer last, outputs the transferred digital signal φ2 toward the processing unit 2 .

In the example of the transfer direction shown in FIG. 7, the transfer of the digital signal φ2 is performed for each of the plurality of radiation detectors 1 arranged in the horizontal direction (parallel transfer for each column). That is, the plurality of radiation detectors 1 arranged in the horizontal direction output the digital signal φ2 from the left end toward the right end radiation detector 1 . Then, the radiation detector 1 at the right end outputs the transferred digital signal φ2 toward the processing section 2 . At this time, the data transfer direction (the direction along the Y axis in FIG. 7) and the transmission direction of the control signal θ between the plurality of radiation detectors 1 may be the same direction along the same transmission path, or The directions may intersect. For example, the transmission direction of the control signal θ from the control unit 3 may be the direction along the X-axis perpendicular to the data transfer direction. In this way, by reducing the number of cascade connections in the data transfer direction, it is possible to read out the digital signal φ2 in parallel at a high speed, while at the same time reducing the number of parallel connections for transmitting the control signal θ. By reducing, the number of control signals θ can be reduced.

In the radiation image sensor 100 described above, each of the plurality of readout circuits 8h in the plurality of radiation detectors 1 outputs a digital value based on the charge generated by each pixel of the charge generator 7. FIG. At this time, the plurality of readout circuits 8h sequentially transfer the data representing the digital values to the adjacent readout circuits 8h according to the control signal from the outside, and then output the data to the adjacent radiation detectors 1 . Such a configuration eliminates the need for wiring for outputting data to the outside via the circuit board 4 in at least some of the readout circuits 8h in the plurality of radiation detectors 1 . As a result, the wiring route for data output is simplified, and the reliability of the output information indicated by the data can be improved. For example, when data output wiring is provided in the circuit board 4 for each of the plurality of readout circuits 8h of the plurality of radiation detectors 1, it is necessary to provide a plurality of wiring layers in the depth direction of the circuit board 4. , the wiring structure becomes more complicated as the number of pixels increases. In contrast, in this embodiment, the wiring structure is easily simplified.

Further, in the radiation image sensor 100, the plurality of readout circuits 8h of one radiation detector 1 are configured to transfer data via all the readout circuits 8h included in one radiation detector 1. there is In this case, the plurality of readout circuits 8h transfer the digital signal φ2 indicating the digital value via all the readout circuits 8h according to the control signal θ from the outside. With such a configuration, more readout circuits 8h in the radiation detector 1 do not require wiring for outputting data to the outside. As a result, the wiring route for data output is further simplified, and the reliability of the output information indicated by the data can be further improved.

In this embodiment, at least one of the readout circuits 8h at the outermost edge among the plurality of readout circuits 8h of the radiation detector 1 receives data transferred from other adjacent readout circuits 8h in response to the control signal. to the circuit board 4. According to this configuration, since the readout circuit 8h at the outermost edge outputs the data transferred from the other adjacent readout circuit 8h to the circuit board 4, the data is sequentially transmitted through the plurality of readout circuits 8h in the radiation detector 1. The transferred data can be output to the circuit board 4 by the reading circuit 8h at the outermost edge. This eliminates the need for wiring for outputting data from the plurality of readout circuits 8h in the radiation detector 1, and the number of wirings connected to one radiation detector 1 can be efficiently reduced. As a result, the reliability of output information can be further improved.

Further, in the present embodiment, at least one of the readout circuits 8h at the outermost edge among the plurality of readout circuits 8h of the radiation detector 1 is the outermost edge of another radiation detector 1 adjacent to the radiation detector 1 concerned. It is configured to accumulate and transfer the data output from the readout circuit 8h of the section. According to this configuration, the readout circuit 8h at the edge of one radiation detector 1 receives data output from the readout circuit 8h at the edge of another radiation detector 1 adjacent to the radiation detector 1. functions to store and transfer Thereby, wiring for outputting data from other radiation detectors 1 can be shortened. As a result, the reliability of output information can be further improved.

In this embodiment, among the plurality of readout circuits 8h of the radiation detector 1, the readout circuits 8h adjacent in the one-dimensional direction are configured to sequentially transfer data in the one-dimensional direction. The readout circuit 8h at the outermost edge in the one-dimensional direction is configured to transfer data to the adjacent readout circuit 8h in a direction substantially perpendicular to the one-dimensional direction. According to this configuration, the data output from the plurality of readout circuits 8h arranged two-dimensionally within the radiation detector 1 are sequentially transferred without omission through short paths between the plurality of readout circuits 8h. . As a result, the number of wires connected from the radiation detector 1 to the outside can be reduced to the maximum. As a result, the reliability of output information can be further improved.

In this embodiment, the radiation detector 1 includes a readout circuit board 8 in which a plurality of readout circuits 8h are formed. It is output to the circuit board 4 via the through electrode 8f penetrating the circuit layer 8b. According to this configuration, the wiring that connects the readout circuit 8h at the outermost edge and the circuit board 4 can be formed within the range of the charge generator 7, and the gap between the plurality of radiation detectors 1 can be reduced. be able to. As a result, it is possible to prevent the occurrence of dead zones in the radiation imaging apparatus.

In one form, the radiation detector 1 comprises a readout circuit board 8 in which a plurality of readout circuits 8h are formed, wherein at least one of the readout circuits 8h at the outermost edge stores data and the circuit board 4. Input is made via a through electrode 8d penetrating through an integrated circuit layer 8b of the circuit board 8. FIG. According to such a configuration, the wiring that connects the readout circuit 8h at the outermost edge and the circuit board 4 can be formed within the range of the charge generator 7, and the gaps between the plurality of radiation detectors 1 can be can be made smaller. As a result, it is possible to prevent the occurrence of dead zones in the radiation imaging apparatus.

The radiation detector of the present disclosure is not limited to the embodiments described above. Various modifications of the radiation detector of the present disclosure are possible without departing from the gist of the claims.

The number of radiation detectors 1 or the number of pixels in the radiation image sensor 100 in the above-described embodiment is an example, and may be changed in various ways.

Moreover, the data output by the radiation detector 1 is not limited to a digital signal indicating the charge corresponding to the energy of the radiation. It may be a digital value obtained by

The arrangement configuration of the plurality of radiation detectors 1 provided in the radiation image sensor 100 does not necessarily have to be two-dimensionally arranged, and may be, for example, one-dimensionally arranged. FIG. 8 is a diagram showing the relationship of the directions of serial data transfer in the plurality of radiation detectors 1 included in the radiation image sensor 100 in such a case. In this modification, the digital signal φ2 is transferred between a plurality of radiation detectors 1 arranged along the horizontal direction. That is, the plurality of radiation detectors 1 arranged along the horizontal direction outputs the digital signal φ2 from the left end toward the right end radiation detector 1 . Then, the radiation detector 1 at the right end outputs the transferred digital signal φ2 toward the processing section 2 .

DESCRIPTION OF SYMBOLS 100... Radiation image sensor (radiation imaging device), 1... Radiation detector, 4... Circuit board, 7... Charge generator, 8... Read-out circuit board, 8d, 8f... Through electrode, 8h... Read-out circuit (read-out part).

Claims (7)

a plurality of charge generation units that generate charges corresponding to the energy of incident radiation or the number of particles; and a plurality of readout units that output digital values based on the charges generated by each of the plurality of charge generation units. , radiation detectors stacked on each other and arranged two-dimensionally;
A circuit board on which a plurality of the radiation detectors are arranged,
The plurality of readout units of one of the radiation detectors,
According to a control signal from the outside, the data indicating the digital value is sequentially transferred to other adjacent readout units, and passes through all the readout units included in the one radiation detector among the plurality of readout units. is configured to output to other adjacent radiation detectors after being transferred to
Radiation imaging device. a plurality of charge generation units that generate charges corresponding to the energy of incident radiation or the number of particles; and a plurality of readout units that output digital values based on the charges generated by each of the plurality of charge generation units. , radiation detectors stacked on each other and arranged two-dimensionally;
A circuit board on which a plurality of the radiation detectors are arranged,
In one of the radiation detectors, the plurality of readout units are divided into a plurality of regions, and each of the plurality of regions has one data input and one data output,
The plurality of readout units included in one of the regions,
According to a control signal from the outside, the data indicating the digital value is sequentially transferred to other adjacent readout units, and transferred via all the readout units included in the one area. configured to output one data output from the readout unit to another adjacent radiation detector,
Radiation imaging device. a plurality of charge generation units that generate charges corresponding to the energy of incident radiation or the number of particles; and a plurality of readout units that output digital values based on the charges generated by each of the plurality of charge generation units. , radiation detectors stacked on each other and arranged two-dimensionally;
A circuit board on which a plurality of the radiation detectors are arranged,
The plurality of readout units of one of the radiation detectors,
In response to a control signal from the outside, the data representing the digital value is sequentially transferred to other adjacent readout units, and output from the readout unit at the outermost edge to other adjacent radiation detectors. is,
The plurality of radiation detectors are daisy-chained and configured to transfer the data representing the digital value via the plurality of radiation detectors.
Radiation imaging device. At least one of the readout units at the outermost edge of the radiation detector among the plurality of readout units transmits the data transferred from the other adjacent readout units to the circuit board in response to the control signal. 4. The radiation imaging apparatus according to any one of claims 1 to 3 , configured to output. At least one of the readout portions at the outermost edge of the radiation detector among the plurality of readout portions of the radiation detector is the readout portion at the outermost edge of another radiation detector adjacent to the radiation detector. 5. A radiation imaging apparatus according to claim 4, configured to store and transfer said data output from. comprising another circuit board in which the plurality of readout units are formed;
5. The radiographic imaging apparatus according to claim 4, wherein at least one of the readout units at the outermost edge outputs the data to the circuit board via a through electrode penetrating the another circuit board. comprising another circuit board in which the plurality of readout units are formed;
6. The radiographic imaging apparatus according to claim 5, wherein said data is input to at least one of said readout units at said outermost edge via a through electrode penetrating through said circuit board and said another circuit board. .

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